Automatic folding and binding machine



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A. SOFFA ETAL AUTOMATIC FOLDING AND BINDING MACHINE July 7, 1959 8 Sheets-Sheet 2 Filed Feb. 25, 1957 July 7, 1959 A. SOFFA ETAL 2,893,297

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July 7, 1959 A. SOFFA ET AL AUTOMATIC FOLDING AND BINDING MACHINE 8 Sheets-Sheet 4 Filed Feb. 25, 1957 wwi v y .1 9 A. 50m Em 2,893,297

AUTOMATIC FOLDING AND BINDING MACHINE July 7, 1959 A. SOFFA E'IAL 2,893,297v

AUTOMATIC FOLDING AND BINDING MACHINE Filed Feb. 25, 195"! 8 Sheets-Sheet 6 /'7& 7.

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. AUTOMATIC FOLDING AND BINDING MACHINE Filed Feb. 25, 1957 a Sheets-Sheet a Haj/5 11v wm/ 7'0 85 4: an: r :1: A r-9 Penna 0r MK mun/e.

United States Patent AUTOMATIC FOLDING AND BINDING MACHINE Albert Solfa, Wynnewood, and Frederick W. Kulicke, Jr., Philadelphia, Pa., assignors to Walter S. Sachs & Co., Inc., Philadelphia, Pa., a corporation of Pennsylvania Application February 25, 1957, Serial No. 642,223

4 Claims. (Cl. 93-84) Our invention relates to an automatic folding and binding machine and more particularly relates to a machine for automatically impressing pleats or folds into a scored flat sheet and binding the plicated sheet within a backer whereby the bound sheet may thereafter be completely unfolded simply by opening the backer, or collapsed into a fraction of the unfolded state merely by closing the backer.

This invention is particularly concerned with the foldable sheet set forth in the patent to Palm, No. 2,525,937, wherein there is disclosed a scored, rectangular sheet having diagonal folding lines extending from each of the four corners to the center of the sheet, a central or primary folding line extending from one edge of the sheet to the opposite edge thereof and bisecting the angle between the diagonal folding lines and supplementary folding lines extending from adjacent edges of the sheet perpendicularly thereto and meeting in pairs on the diagonal folding lines, the folding direction of the central folding line and the portions of the diagonal folding lines outside the points of intersection with the supplementary folding lines being the same and opposite to that of the remainder of the folds, and a folding backer for the foldable sheet, the central fold line of the sheet coinciding with the fold of the backer and the sheet being attached to said backer on opposite sides of its fold thereof.

In the past, the foldable sheet shown in the aforesaid Palm Patent No. 2,525,937, the folds or pleats had to be formed or impressed by hand, thereby requiring a time consuming expensive operation.

It is, therefore, an object of our invention to provide an automatic folding machine for impressing pleats into a scored sheet to form a foldable sheet of the character set forth herein.

Another object of our invention is to provide a machine for automatically impressing pleats into a scored sheet and "binding the foldable sheet within a hacker whereby opening of the hacker will cause the sheet to completely unfold so that the whole face thereof is visible, and closing the backer will collapse the sheet into a small fraction of its opened condition.

Another object of our invention is to provide an automatic folding and binding machine whereby stacks of scored sheets and backers may 'be automatically fed therein to be folded and attached to each other in assembled relationship.

Other objects of our invention are to provide an improved device of the character described, that is easily and economically produced, which is sturdy in construction, and which is highly efiicient in operation.

With the above and related objects in view, our invention consists in the details of construction and combination of parts, as will be more fully understood from the following description, when read in conjunction with the accompanying drawings, in which:

binding machine embodying my invention.

2,893,297 Patented July 7, 1959 Fig. 2 is a side elevational view thereof.

Fig. 3 is an end elevational view thereof.

Fig. 4 is a sectional view taken along lines 4-4 of Fig. 1.

Fig. Fig. 4.

Fig. Fig. 5.

Fig. Fig. 4.

Fig. Fig. 7.

Fig. Fig. 7.

Fig. 10 is a sectional view similar to Fig. 8 showing the first step of the folding operation.

Fig. 11 is a sectional view of the folding mechanism illustrating a more advanced stage of the pleating operation,

Fig. 12 is a sectional view of the folding mechanism illustrating the final stages of the pleating operation.

5 is a sectional view taken along lines 5-5 of 6 is a sectional view taken along lines 6-6 of 7 is a sectional view taken along lines 7-7 of 8 is a sectional view taken along lines 8-8 of 9 is a sectional view taken along lines 9-9 of Fig. 13 is a sectional view taken along lines 13-13 of Fig. 10.

Fig. 14 is a sectional view taken along lines 14-14 of Fig. 11.

Fig. 15 is a sectional view taken along lines 15-15 of Fig. 12.

Fig. 16 is a plan view of the sheet in the blank or unfolded state, the dotted lines representing pre-scored lines along which plication is to occur.

Fig. 17 is a perspective view of the foldable sheet in its initial phase of creasing.

Fig. 18 is a perspective view of the foldable sheet in a further stage of the folding operation.

Fig. 19 is a perspective view of the foldable sheet immediately prior to its final folded position.

Fig. 20 is a perspective view of the foldable sheet in final position as a cover or backer sheet is to be bound thereabout.

Fig. 21 is a perspective view of the backer and the foldable sheet bound therein, both being in completely folded position.

Referring now in greater detail to the drawings in which similar reference characters refer to similar parts, we show an automatic folding and binding machine comprising, a sheet feeding section, generally designated as A, a sheet folding section, generally designated as B, a backer feeding and gumming section, generally designated as C, and a binding section, generally designated as D, whereby a scored sheet, generally designated as B, may be automatically pleated and combined with a hacker, generally designated as F.

A preliminary outline of the principal motions as articulated by the drive mechanism will facilitate an understanding of the details to follow.

Referring to Figs. 1 and 3, a stack of the scored sheets E are set within the sheet feeding section A at the extreme right hand side of the machine whereby each sheet is elevated and picked up by a vacuum operated pick up shoe one-at-a-time to be deposited upon tape conveyors for transmission to the sheet folding section B in lined relationship with respect to the operations which are to be performed thereon. Each sheet has already been scored in a conventional manner as shown in Fig. 16,v wherein a central or primary scored line extends frommentary lines 22 and 24 extend perpendicularly from adjacent edges of the sheet E and intersect in pairs on respective diagonal lines 14, 16, 18 and 20, the outer portions of each of the diagonal lines being designated as "'25. The arrows indicate the direction of travel for the sheet E as the sequencefof operations is performed thereon. The direction of -travel-of the sheet E in-the feeding section A is 'axial 'With the primary line -10, -12.

The sheet folding section B 'captures the scored sheet E'and preferentially causes pleats to be formed therein whereby the direction of the :plication of the primary line '10, I2 and'the diagonal extension lines 25 are all upward from the plane of the face of the foldable sheet E whi-le interior diagonal lines 14, '1'6, 18 and 20 and the supplementary lines 22 and 24 are all downward from the plane-of 'the race of the foldable sheet. The progressive folding of the sheet E produced by the folding sectionB, is shown respectively in Figs. 17, 18 and 19 Plan views of the machine folding mechanism are shown in Figs. '1 and 7 and end on views of the sequence of operation of the folding mechanism along the primarylines 10', 12. are illustrated in Figs. 8, 10, 11 and 12, Fig. 9 being anen'larged view of a half-folding mechanism. Side views of the operational sequence for the supplementary lines 22, 24 and'25 are shown in Figs. 13, 14 and 15.

After the preferential direction of the various fold lines has been formed, a ram pushes the crumpled sheetout o'f'the folding mechanism into an ironing conveyor where each fold is positively impressed preparatory to comhitting the sheet E with the hacker F. See Fig. 4.

The backer F is stacked in'a similar manner, see Fig. 2, left hand side within the backer feeding and gumming section C, and is transported in synchronization with the foldable sheet E at right angles to the direction of travel of the latter into the binding section D. The backer F in its blank state, comprises a rectangular, .gencrally rigid cardboard sheet, centrally scored at 26 to divide it into symmetrical front and back cover portions 27 and 28 respectively, for binding about the foldable sheet E. See Figs. and 21. The backer F in its unfolded state is automatically conveyed through the hacker feeding and gumming section C whereby the scored line 26 is perpendicular to the direction of its travel. Gum is applied by a suitable applicator in strips on the interior faces of the cover portions 27 and 28 adjacent their longitudinal edges. The progress of the backer F is shown in Fig. 4 where after being transported into the bending section, it is stopped and positioned therein preparatory to receipt from above of an already pressed foldable sheet E. In this regard, the backer F is partially tucked at this stage along scored line 26 into a gull wing shapeso that engagement of the pressed foldable sheet E will not destroy the point of the latter when feeding contact is made. Continued forced downward motion of the foldable sheet B will force the backer F into the nips of a set of compressing rollers which will firmly adhere the gum on the backer against the foldable sheet and press the assembly into the bound book shape shown in Fig. 21. The assembled bound sheets are then dropped into a receptacle where they are automatically stacked in a vertical file.

Drive unit As seen from Figs. 1, 2 and 3, the plan structural arrangement of the machine is in the form of a T comprising a main frame 30 defining the cap of the T and an auxiliary frame 31, defining the leg thereof. The auxiliary frame 31 contains merely the backer feeding and gumming section C while the main frame 30 supports the remaining operational sections including the power or driving transmission. A variable speed drive motor 32 is coupled to a main cam shaft 33 through a chain and sprocket drive 34; the main shaft 33 being rotatably supported in suitable bearings wit-hin a pair of upright frame members 35 and 3.6. See Figs. 2 and 3. A, ram cam 37 mounted at one end of the-main,- shaft '33 whereby the pli'cated sheets in the folding mechanism of section B may be ejected therefrom for subsequentbinding in proper synchronization. A second cam 38 on the mainshaft 33 controls the pivotal operation of the folding mechanism about the primary lines 10, 12 of the foldable sheet B. At the end of the mainshaft 33 opposite to that of the ram cam is mounted an eccen ric 39 which controls the stacking of the completely assembled and backed sheets. The structural arrangement and operations of the foregoing will be described in greater detail in a subsequent portion of the specification dealing specifically with the particular operationinvolved. The mainshaft 33 is coupled to a jack shaft 40in a 1 ratio through a chain and sprocket drive 41, the latter also being rotatably supported within the main frame. See Fig. 3. A jack shaft exten sion 42 is coupled to the right hand end of the jack shaft 40 and is rotatably supported within suitable bearings of the frarne member 36 and a'second upright frame member 43. The jack shaft extension extends beyond the upright frame member 43 and has a chain and sprocket drive 44 mounted thereon which operates the conveying system of the feeding section through-a chain drive 45 and a miter drive 46. The extreme right hand end of the jack shaft extension 42 as shown in Fig. 3, has an eccentric 47 which in its rotatable cyclic actuation functions to elevate the stack of scored sheets E and further operates a vacuum-operated, pick-up shoe through a rod 48.

Sheet feeding section The sheet feeding section A comprises a frame stand 50 which supports a receptacle 51, the receptacle maintaining deposited sheets E in stacked relationship preparatory to feeding, see Fig. 3. An automatic, vacuumoperated pick-up shoe '52 is coupled through a linkage system (not shown) to the rod 48, the latter of which re'ciprocates as rotation of the jack shaft 40 and its extension 42 thereof. Thus the pick-up shoe 52 is pivotally and hingedly supported whereby its position shifts to 'a location directly over and touching the uppermost sheet in the stack, vacuum being applied to the bottom of the "shot through a valve cam (not shown) on the jack shaft. Further rotation of the jack shaft causes the pick-up shoe 52 to shift'into a position shown in Fig. 3, where the uppermost sheet of paper is adhered to the bottom of the shoe and is about to be set upon the conveying tape mechanism. A paper thickness micrometer 53 gauges the thickness of the sheets of paper by a pair of rollers 54 and prevents two sheets E from being deposited upon the conveying mechanism should such a condition occur by virtue of static attraction or otherwise. The second sheet is rejected from being deposited upon the conveyors by a pivotally operated rejection blink 55 connected to the paper thickness micrometer system 53 and54.

The conveying system for the sheet feeding section A comprises a pair of centrally located conveying tapes 56 and a plurality of conveying belts 57 positioned outwardly therefrom on either side thereof as shown in Fig. 1. These tapes and belts are rotatably supported within side supports 58 and are driven as hereinbefor'e set forth by the chain drive 45 coupled to the jack shaft 40, and act to support each sheet of paper E and convey each sheet linearly between guides 59 into the sheet folding section B. It is to be noted that the lengths of the tapes 56 are longer than the lengths of the belts 57, the former extending between the folding mechanism whereby support for each sheet of paper is provided as will be more fully described herein immediately below.

wings 60A and 60B, each of which is a mirror image of; the; other during all phases 'of the folding operation.

All component parts 'of'the-folding wings 60A and 60B therefore have the appendages A and B respectively in the drawings'as reference is made to mirror imaged parts. Each of the wings 60A and 60B comprises an angle frame 62A and 62B respectively, each frame 62 having bearing housings 64A, 64B and 65A, 65B secured thereto which are 'hingedly supported upon a wing pivot shaft 66. See Figs. and 6. Connecting rods 67A and 67B are pivotally secured to the housings 64A and 64B respectively at their rod ends 68A and 68B. The lower ends of the connecting rods 67 also have eyelet rod ends 69 between which is rotatably supported a cam follower 70 on a shaft 71. The cam follower 70 contacts the surface of the cam 38 which is of a substantially cardioid shape whereby a single rotation of cam 38 causes the wings 60 to hingedly pivot toward each other and then to return as shown in Fig. 6.

The forward portion of the wings 60 adjacent the sheet feeding section A each has a platen 72 secured to the upper surface of angle frame 62 and each platen has a regular trapezoidal shape. Platen 72A conforms to the portion of the sheet E bounded by the lines 24-18-0- 2024, while platen 72B coincides with the area bounded by lines 24140-1624. See Fig. 7. Immediately above each platen 72 is a sheet metal, hold-down fin 73 which substantially conforms to the contour of each platen. The exterior portion of each hold-down fin 73 is secured to a right angle bracket 74, the latter being coupled through a flat spring 76 to a housing 75' at the outer transverse portion of the wings. See Figs. 7 to inclusive. When the wings 60 are in a position to receive a sheet E from the feeding section, the holddown fins 73 are hingedly spaced from their respective platens 72 by a riser pin 77 which is slidably supported in each platen 72. That is, when the platens 72 are in sheet receiving position, they lie in a single horizontal plane, and a riser bracket 78, secured to te machine frame (not shown), engages the riser pin 77, causing the pin to slide upwardly and press upon bracket 74 whereby the hold-down fins 73 are urged upward. See Fig. 9. Since the spring 76 endeavors to resiliently urge the holddown fins 73 into contact with its respective platen, pivotal movement of the wings 60 toward each other releases the contact of the riser pin 77 from the riser bracket 78, thereby enabling the hold-down springs 76 to force the fins 73 against the platens 72 to firmly secure a foldable sheet E therebetween. See Fig. 10.

At each of the parallel sides of the trapezoidal platens 72 is arranged a folding wing tab 80A, 80B and 82A, 82B, each folding tab being triangular in shape and adapted to pivot at right angles to the path of travel of the foldable sheet E. See Figs. 7, l3, l4 and 15. The tabs 80 and 82 are mounted upon bracket shafts 83 and 84, rotatably supported within the housings 75 at the exterior sides of the wing sections 60A and 60B. Spur gears 85 and 86 are mounted on the outboard end of the shafts 83 and 84 and intermesh respectively with pinion gears 87 and 88. The pinion gears 88A and 88B are mounted upon shafts, the inboard end of which have a set of miter gears 89A and 89B respectively driven by shafts 90A and 90B respectively longitudinally extending with and rotatably supported on the underside of the wing angle frames 62. The end of each shaft 90 has an arm 91 secured thereto rotatably supporting a cam follower 92. See Figs. 1 and 2. The cam followers 92A and 92B take the path of travel of oppositely disposed grooves in a stationary cam track 93 as a push-pull system whereby tabs 80A, 80B and 82A, 82B fold upon one another respectively as shown in Figs. 13, 14 and 15.

The folding operation upon the scored sheet E is as follows: as each sheet is fed from the sheet feeding section A in timed relationship: Referring to Figs. 5, 7 and 8, each scored sheet is conveyed from the tapes 56 into the folding wings 60 between the platens 72 and the hold-downs 73 until the sheet engages stops 94. It is to be observed from Figs. 5 and 13, that the forward portion of wing tabs are slightly dipped from a horizontal plane as each sheet E is about to be received in the folding section and that the tapes 56 project into and between the wing tabs. Suitable guides axially align each sheet E along score lines 10, 12 centrally with respect to the pivot of the wings. Synchronized rotation of the cam 38 causes the wings 60A and 60B to fold slightly toward each other whereby the riser pin 77 is released to enable the hold-downs 73 to lock the scored sheet against the platens 72. Immediately subsequent to the bottoming of the hold-downs 73, a stream of air is directed upwardly from nozzles 95 situated axially between the folding wings and cause scored lines 10 and 12 to preferentially fold upwardly toward each other. This stream of air is actuated by a valve (not shown) cam operated from the jack shaft 40 and cuts off when the folding wings 60 attain a position approximating that shown in Fig. 11. As the wings 60A and 60B fold toward one another, they cause fold lines 10 and 12 in the foldable sheet to be forced upward from the plane of the paper while lines 14, 16, 18 and 20 are forced downwardly, the sequence of operation being shown consecutively in Figs. 10, 11 and 12. Simultaneously with the folding of the wings 60A and 60B, the tabs 80 and 82 pivot toward each other as shown sequentially in Figs. 13, 14 and 15, whereby the four fold lines 25 are directed upwardly from the plane of the sheet while intersecting lines 22 and 24 are directed downwardly, it being observed that the hypotenuse of the tabs 80 and 82 corre sponds respectively with outer diagonal lines 25.

Referring to Figs. 3, 4 and 5, the cupped sheet E is forced by the ram 96 into a conveyor for positively impressing or ironing the preferentially folded lines, endless belts 100 and 101, each driven by timing gears 102 and 103 respectively. A plurality of conveyor idler rollers 104 and 105 direct the path of travel of the sheet downwardly between a set of ironing or compressor rolls 106 and 107, spaced on either side of the belts 100 and 101. Adjustable idler rollers 108 maintain the proper tension upon the belts. The timer gears 102 and 103 are rotatably supported in shafts 104 and driven by a jack shaft 109 and chain and sprocket 110 from the mainshaft 33. The ironing rolls 106 and 107 are mounted on shafts 111 driven by pulleys 112, also from shaft 109.

Thus, the cupped sheet E is forced by the ram 96 so that the vertex 0 of the sheet is engaged between the nips of rolls 104. The sheet is then carried downwardly whereupon the ironing rolls 106 and 107 compress it to a fiat folded state shown in Fig. 20, preparatory to insertion into a backer F for binding therein.

Backer feeding and gumming section The backer feeding and gumming section C comprises a frame stand which supports a receptacle 121, wherein a plurality of stacked backers F are maintained preparatory to feeding as shown in Fig. 2. The stand 120 and receptacle 121, are generally identical to the structure described under the sheet feeding section A. A vacuum operated pick-up shoe 122 lifts the uppermost backer F and deposits it in timed sequence with the other machine operations upon a conveyor belt 123, wherein the central scored line 26 is perpendicular to its direction of travel. It is to be observed from Fig. 2 that the pick-up shoe 122 and the conveyor 123, operate from a separate motor 124 and drive 125, and are not synchronized with the main power motor 32.

It is, therefore, necessary to utilize a synchronizing device for properly timing the backer F in sequence with the operations performed on the sheet E.

A finger stop 126 is pivotally mounted at the exit end of the conveyor 123, and this finger stop is linked to a crank cam 127 and connecting rod 128. The connecting rod 128 is pivoted to an eccentric 129, which rotates in a one to one ratio with the main shaft 33 through chain drive 130. Thus, the hacker F will only be conveyed into 7 thelhifidin'g'section Dwh'enth'e finger stop 126 is raised iit'isynchrohizationwith the other operations. 7 y j t Ks'shown 'n Figs. 2 and 4, apair of hip rollers 131 and apair of conveyor rollers 132 have an'e'ndle'ss belt 133 stretched thereabout which is driven by 'a pressure roller ,13'4, synchronized with 'the main shaft through chaindrive 135. Immediately above'the pmssnr'emua 1'34isrot'atably supported a plurality of applicator renew l 3'6,"'each'having'a pair of circuriiferentially spaeea'wiper hlad'es 1'37, which 'rotatably engage a roller 138 mounted in a gumpot 139. As the backer F passes betweenthe pressure'roller 134 and the applicator rollenthe wiperjhlad'es 137 deposit a central strip ,and'two outside strips'or gum upon the backer on each side'of the'ceiitr'alscoredline 26. The backer F with the wet gu'm'strips thereon on its upper surface is then transported upon conveyors 140 for binding about the 'folded sheet E.

Binding section 'The scored backer "F is fed into the binding section D across split gull-Wing plates 142 and 143 and is positioned by a stop 144 whereby the scored line 26 is immediately above the center portion of the split. See Fig. 4. A tucking finger 1'45 on the end of an arm 146 is hingedly supported above the scored line 26, and, in its downward oscillating position, the finger creases the backer F intoa gull-wing shape between idler rollers 147. This preliminary creasing prevents crumpling of the point'ofthe'c oinpressed sheet E as the latter descends fromthe she'etifol'ding section B above. 'See Fig. 20. When the downwardly descending compressed sheet E'isurged into contact withthe backer F along line 26, the front and back portions 27 and 28 of the backer are urged upwardly and ,enwrap the sides of the compressed folda'ble sheet. Further downward progress of the foldable sheet forces the combination of backer F wrapped about the sheet through a pair of compressing rollers 148 which are driven from the chain drive 110. The compressingrollers I48 firmly adhere the already gummed backers 'F to the sides of the foldable sheet E by ironing the two together as shown in Fig. 21.

The backer enwrapped sheets then fall downwardly into a stacking receptacle 150 having a stack'support 152 against which an oscillating stacker arm 154 vertically stacks the foldable sheets in face to face contact with each other. Ratchet means (not shown) prevent the already stacked sheet from falling back into the path of travel of a subsequent sheet passing down from above. It is to be observed that the hinged operation of the stacker arm 154 is synchronized with the remainder of the performed operations through crank 156. See Fig. 2.

Although our invention has been described in considerable detail, such description is intended as being illustrative rather than limiting, since the invention may be variously embodied, and the scope of the invention is to be determined as claimed.

We claim as our invention: p

1. An automatic folding machine for plicating and assembling a foldable sheet and backer of the character described comprising a frame, a pair of opposed folding wings pivotally mounted on a horizontal axis in said sfaid wi'ngs, asten of sfaid'plaiens having. aniapex conform-- iii'g tojdia gohalscoredlines' or a sheet to be folded thereon, a sheet nietalholdi-down resiliently hinged to'the outboard endi'ot each of 'said'win'gs and'having 'a'pl'an configuration,respectively'registering with said platens, a riser on each of said lwingsin detachable engagement with the respective hold down and spacing [said hold-down from the respective platen when said "wings are. horizontally aligned, a pair of opposed triangular tabs pivotally mounted upon respective lateral edges or each'vofsaid platens, and airjet rneaiis in :saidfr'ame disposed along the 'fold'lin'e of said wings wherehy the sheet ofpaper will be clamped snugly'between saidhold-downs and said platens, said win'g's being folded upwardly together as mirror images while. the air 'jet is impressed upon the lower surface of said sheet, and said tabs are pivotally urged into abutment with said hold-downs. I p

2. .The 'inventionof claim 1 wherein a vertically reciprocating'fam is modified in said frame above said wings and on an axisperpendicularto thejh'orizontal axis thereof, and carnnieaiis ''downwardly urging said ram upon the upper edges of the sheet folded within said wings whereby the'folded sheet will be slidably forced out of said wings. p

73.. An automatic folding machine for plicating and .assembling a foldabl'e sheet and backer of'the character described comprising a frame, a pair of platens, each pivotally -rno1inted in said trameion a respective horizontal axis, said :platenseach'having'a rectangular portionwith a regular trapezoidal apex extending therefrom, said apices heing'adjacently spacedalong afrnedi'al fold line as mirror images offone another, a flat hold down fin resiliently hinged to the outboard end of each of said platens and having a plan configuration registering therewith, riser means to space said hold-down fins above said platens respectively, a pair of triangular tabs pivotally secured to the respective lateral edges'of the rectangular portions of each of said platens, and ,air jet means mounted in said framealong the medial fold line, cam means in said frameto upwardly urge said platens toward each other from a single horizontal plane into abutting vertical planes, gear means synchronized with said cam means to simultaneously urge each of said tabs from a horizontal plane outwardly extending from said platens through of arc into a plane abutting saidfplatens.

4. The invention of claim 3 wherein an ironing conveyor ismounted in said frame belc aw said platens, said ironing conveyor'comprising a; pair of endless belts having vertically abutting surfaces, a pair ofironing rollers having the surfaces thereof tangentially disposed against the respective belts, and a ram vertically reciprocating in said frame above said platens urging the sheet folded therein slidably therefrom into engagement with said ironing conveyor.

Sturtevant Jan. 5, 1909 Peterson Jan. 29, 1952 

